February 2023: Dense fog and harmful air pollution in Hanoi
On the morning of the 3rd February 2023, Hanoi was engulfed in fog and light rain, making it difficult for traffic and the daily of people. Pollution is likely to last in Hanoi until mid-February because the main weather in the coming days is drizzle and humidity.
At 6am, according to the monitoring data of Pam Air, the AQI index at points in Hanoi fluctuated mainly 150-200 units, the threshold harmful to human health. Particularly, some points have high AQI over 200 units. IQAir forecasts that air pollution is likely to last longer and be more severe in Hanoi in the days between the 4th and 6th February. At this time, the average pollution index ranges from 17-180 units, which are harmful levels.
According to the Hanoi Department of Environmental Protection, the reason for the increase in air pollution in Hanoi at this time is due to the weakening of the cold air, which causes dust and dirt to not be diffused but accumulated from traffic and construction activities. In addition, fog, increased humidity and warmer weather are also conditions that cause air quality to decline.
Notably, some neighbouring provinces and cities such as Bac Ninh, Thai Nguyen and Bac Giang maintain air quality at hazardous levels when the AQI is above 300 units. Meanwhile, this index improved more in the Northern mountainous region. Some places like Lao Cai, Bac Can, Phu Tho have good air with AQI below 50 units. The monitoring map also shows that in the area from the Central Coast, the Central Highlands to the South, the air quality is mostly good. Some scores recorded AQI at a harmful threshold but could improve in the coming hours. In Ho Chi Minh City, the AQI at 6 am this morning was at a fresh and good level.
In the second half of February, the new area can receive more intense cold air waves causing severe cold and harmful cold. At this time, the air quality has the potential to improve markedly.
Source: the Internet